Morphological study on lateral surface of tibia bone with reconstruction technique of spiral CT

Objective: To study morphologic characteristics of the distal tibia, for the purpose of offering anatomical foundation for the design of anatomical plate of distal tibias for the domestic population, as well as for the plating of tibia fracture. Methods: 80 human tibia bones from alive adults were scanned by spiral CT and the three dimensional images were reconstructed with SSD method. Several anatomical indices were measured by correlated software on the base of three dimensional images, including the length of twisting segment on the lateral surface of the tibia, twisting angles on different twisting segments and the anteversion angle of the lateral surface of the tibia. The measured indices were statistically analyzed with alive individual whole information. Results: Length of the twisting segment of the lateral tibia surface was 12.9±0.41cm in male and 12.34±0.31cm in female. Twisting angle of lateral surface of tibia was as follows: in the first quarter, the twisting angle of the lateral tibia surface was 13.98±2.72° in male and 13.38±3.11° in female. In the second quarter, it was 32.49±3.66° in male and 31.85±3.86° in female. In the third quarter, it was 55.18±3.53° in male and 50.95±6.24° in female. In the fourth quarter, it was 82.13±2.89° in male and 72.45±4.81° in female. Anteversion angle of the lateral surface of distal tibia was 7.34±0.91° in male and 6.20±0.41° in female. Conclusions: Twisting angles of lateral tibia surface are different in the different segments. Difference of gender and body height should be considered while designing the twisting and anteversion contour of the tibia anatomical plate for the domestic population. Fixation results may be concerned with the position and the size of the implantation.